The present invention relates to a device for the preventive support of femoral regions. It has been observed in the medical world, and in particular the orthopedic branch of medicine, that the number of hospitalization cases involving bone fractures has risen considerably over recent years, with a large proportion of such fractures affecting the hip region.
One reason for a greater abundance of fractures is to be found in the increasing growth of the elderly population, and therefore in a higher incidence of osteoporosis, i.e. the process, ocurring typically in old age, by which bones become thin and brittle through lack of calcium.
The bone formations tending more than others to be affected by osteoporosis are those characterized by a "cantilever", such as the femur-pelvis structure. More exactly, the proximal extremity of the femur, comprising the ball, the neck and the topmost part of the diaphysis, is required to support the weight of the body, which, bearing down on the ball of the femur, is transmitted to the diaphysis through the lever arm afforded by the narrow neck of the bone. As discernible from FIG. 1 of the drawings attached to the present specification, the group of elements in question broadly resembles an upturned `L` on which the weight of the body impinges directly from above, in such a manner that the resulting vertical force FV is applied to the projecting end of the horizontal member of the upturned `L`; accordingly, this same projecting member (the ball TF) tends to bend, or if stressed beyond a certain limit, to fracture at the junction with the vertical member of the `L` (at the base B of the neck CF). Required as it is to withstand the dynamic stresses generated daily in ambulation, the physiological composition of the femur presents a structure of osseous lamellae arranged in bundles and disposed along lines coinciding with the mechanical forces to be accommodated: a first pair of such bundles (denominated principal and secondary traction) extending from the proximal lateral extremity of the diaphysis substantially up to the extremities of the ball and neck, and a second pair of bundles (denominated principal and secondary compression) extending from the proximal medial extremity of the diaphysis to the uppermost part of the ball and the neck.
Osteoporosis is essentially the process by which the ends of the osseous lamellar structures become thinner to the point ultimately of exposing an area less able to withstand the load normally applied; the area in question, known as Ward's triangle, is located at the base of the neck portion where most femoral fractures typically occur.
With the recent advent of computerized X-ray bone scanning methods, consultants are provided with a swift, secure and precise evaluation of the state of regression of the aforementioned bundles, and therefore with a basis on which to assess the risk of fracture a patient is likely to encounter unless suitable corrective action is taken.
Hitherto, at all events, the problem in question has been addressed by medical/orthopedic research only in terms of post-fracture remedies; in effect, the prior art embraces orthopedic solutions (for example plates and pins) designed and applied so as to allow the rehabilitation of a fractured femur (see also EP 311,556 and EP 425,472) according to the type and localization of the fracture and the age of the patient.
In the light of the foregoing, it may be asserted that there are currently no systems, or at least that there have as yet been no specific solutions or devices researched and developed, designed to prevent a possible fracture of the femur caused by osteoporosis, notwithstanding the availability of methods by which to examine the condition.
Accordingly, the object of the present invention is to provide a device structured in such a way as to afford a preventive means of support applicable to the proximal extremity of the femur, for patients exposed to the risk of fracture due to regression of the osseous lamellar bundles in cases of femoral osteoporosis, such as can be inserted swiftly, in a normal surgery environment, and offer a secure and economically accessible solution for the patient.